1. Field of the Invention
The present invention relates to an endoscopic high-frequency treatment tool for cauterizing and cutting the stem of a polyp and other tissue masses with a high-frequency current.
2. Description of the Related Art
High-frequency snares are extensively used with endoscopes to remove polyps. The snare includes a flexible sheath in the form of an insulated tube, a conductive manipulating wire passed through the sheath, and a looped wire connected to the tip of the manipulating wire. The operator moves the manipulating wire back and forth along its longitudinal axis, so that the looped wire is constricted or expanded at the tip portion of the flexible sheath.
To remove the polyp with the high-frequency snare, the looped wire is placed around the stem of the polyp. The looped wire is then gradually tightened while a high-frequency current is applied thereto. During this tightening process, there is a gradual cauterizing from the outer surface of the polyp to the inner part.
However, this related high-frequency snare has one serious problem. When the operator pulls the manipulating wire applied with a high-frequency current, the caustic effect of the current starts to cut the outer part of the polyp, but at the same time the constricted looped wire may mechanically tear off a portion of the inner part of the polyp which is not fully cauterized by the high-frequency current, thereby causing bleeding.